1. Field of the Invention
The field of the invention primarily relates to a brake pedal sensor and a stop lamp lighting device, which detect depressing of a brake pedal in a vehicle and light a stop lamp.
2. Description of the Related Art
In recent years, as vehicles are becoming more sophisticated in functionality, a stop lamp lighting device for detecting abrupt depressing of a brake pedal and blinking a stop lamp is increasingly widespread.
FIG. 8 is a block diagram of conventional stop lamp lighting device 10.
Stop lamp lighting device 10 determines to either light or blink stop lamp 4 by judging abrupt depressing of a brake pedal from abrupt reduction in vehicle speed.
Stop lamp lighting device 10 includes stop lamp switch 1, lighting determination unit 2, stop lamp lighting control unit 3, stop lamp 4, and vehicle speed sensor 5.
Lighting determination unit 2 is provided with determination section 6 and blinking signal generating section 7. Vehicle speed signal Sg1 is inputted into determination section 6 from vehicle speed sensor 5, and determination section 6 determines whether the vehicle is reducing speed at a deceleration not lower than a predetermined one. Blinking signal generating section 7 generates blinking signal Sg2 in the case of the vehicle reducing speed at a deceleration not lower than the predetermined one. Lighting determination unit 2 transmits blinking signal Sg2 to stop lamp lighting control unit 3 in the case of the vehicle reducing speed at a deceleration not lower than the predetermined one, and transmits lighting signal Sg3 to stop lamp lighting control unit 3 in the case of the vehicle reducing speed at a deceleration lower than the predetermined one.
Stop lamp lighting control unit 3 is provided with logic circuit 8 and drive circuit 9. Blinking signal Sg2 or lighting signal Sg3 is inputted into logic circuit 8. Logic circuit 8 is connected to stop lamp 4 via drive circuit 9, and blinks stop lamp 4 in the case of blinking signal Sg2 having been inputted, or lights stop lamp 4 in the case of lighting signal Sg3 having been inputted.
As thus described, conventional stop lamp lighting device 10 needs to be provided with lighting determination unit 2, stop lamp lighting control unit 3, and vehicle speed sensor 5 other than stop lamp switch 1 and stop lamp 4.